Magnetic Resonance Imaging (MRI) is one of the most widely used imaging tools in medicine for understanding, treating and preventing diseases. The limitations of MRI include low sensitivity and resolution. The sensitivity of existing contrast agents based on Gd and iron oxide nanoparticles remains insufficient. Innovations are needed to develop new, potent contrast agents to enhance the sensitivity and thus capability of MRI in medical research and clinic. Crystalline iron-cobalt (FeCo) alloy exhibits the highest saturation magnetization among all materials, but has not been used for biological and medical applications thus far due to various materials limitations. This application will develop FeCo nanocrystals encapsulated by a single- layer of carbon grapheme into a new, advanced material for MRI. The single-shell grapheme coating protects the FeCo core from degradation and imparts high biocompatibility. The highly magnetic FeCo core affords superior magnetic relativities to conventional agents for MRI. Overall, this application aims to fully develop grapheme-FeCo nanocrystals into a new MRI contrast agent with unprecedented sensitivity, long blood circulation and specific targeting ability. MRI with high spatial resolution down to ~25<m will be developed and combined with the grapheme-FeCo contrast material. The target specific, long circulating and highly sensitive nanocrystals combined with high resolution MRI will then by used for imaging of tumor, angiogenesis and cancer therapy in animals by drug delivery and grapheme hyperthermia monitoring by MRI. Innovations of the application include new nanotechnology approach to biocompatible materials with advanced properties and new grapheme functionalization methods for dense and branched PEGylation and long circulation. The large surface areas of grapheme shells will be exploited to load great numbers of cancer drugs and targeting ligands for delivery to tumor targets monitored by MRI. The grapheme shell will also be used convert near infrared light into thermal energy for hyperthermic treatment of tumors. High resolution MRI enhanced by highly sensitive and long circulating contrast agent will greatly improves the ability of MRI of cancer angiogenesis for understanding cancer progression, metastasis and response to treatment. Thus, this project will develop a new contrast agent that can improve the capabilities of MRI in all areas of medicine. It will also be applied to cancer research to glean tumor structures and angiogenesis, and to develop new cancer therapy. PUBLIC HEALTH RELEVANCE This project will apply the principles of nanotechnology to develop a new type of magnetic nanocrystals for both high resolution MRI for cancer imaging and MRI monitored delivery of anti- cancer drugs to tumors. These technological advances will provide doctors with both a greater understanding of cancer and more powerful tools for its treatment.